In order to switch a vehicle between two-wheel and all-wheel drive, typically, an electromechanical actuator means is used (see, for example, U.S. Pat. No. 5,788,008 to Fort). In order to secure such a vehicle in either a two or all-drive position, often, an electronically controlled axle locking mechanism is applied to an electromechanical actuator means.
However, automotive manufacturers have new requirements for an axle disconnect system, which must disconnect the torque path from wheels to a ring gear, on request, during normal driving. In addition, noise, vibration, and harshness requirements are becoming more stringent, while response time of no more than 200 milliseconds from a time of receiving a command signal is required. Further, drag torque should be minimized across the vehicle operating speed range.
Unfortunately, conventional connecting, locking, and disconnecting axles systems, which are based on electromechanical actuators, are not capable of achieving these new requirements. In addition, the more stringent noise, vibration, and harshness requirements, and response time of no more than 200 milliseconds from a time of receiving a command signal cannot be met by conventional systems.
Consequently, what is sought is a means to achieve these new requirements without increasing the material and labor costs involved. These means need to also improve the reliability and efficiency of vehicle operations.